Scenario: a person adopts a pet

Given a person named Pietro
And a person named Mede
Given a pet named Fido
When Pietro adopts Fido
Then Pietro owns 1 pets
Then Mede owns 0 pets
When Mede adopts Fido
Then Mede owns 1 pets

Scenario: a person adopts three pets
Given a person named Pietro
Given a pet named Fido
And a pet named Micio
And a pet named Gatto
When Pietro adopts Fido
When Pietro adopts Micio
When Pietro adopts Gatto
Then Pietro owns 3 pets